MPEG2 used to require dedicated PCI-[eX] cards to offload the encoding from the CPU as the CPU couldn't do it fast enough to handle real-time. Now CPUs can do multi-times real speed. H.264 also had add-on cards to enable faster than CPU encodes. Now, CPUs handle. Currently, H.265 pushes CPUs to their limits. Tomorrow? H.265 will be fast, and the next H.2xx will be causing us to wait. Rinse. Lather. Repeat.